Sewer flooding control system

ABSTRACT

AN IMPROVED SEWER FLOODING CONTROL SYSTEM UTILIZED TO PREVENT THE FLOODING OF A BUILDING BASEMENT BECAUSE OF A BACKUP IN THE BUILDING SEWER OR THE SURGING OF SEWAGE IN THE SEWER. THE IMPROVED SEWER FLOODING CONTROL SYSTEM IS MOUNTED BELOW THE FLOOR LEVEL OF A BASEMENT TO BE PROTECTED AND IS ACTUATED BY THE PRESENCE OF SEWER FLOODING CONDITIONS IN THE SEWER. THE IMPROVED SYSTEM ALSO PROVIDES NOVEL MERANS FOR PREVENTING FLOODING OR DAMAGE AS A RESULT OF SURGING SEWAGE BOTH IN THE BASEMENT AS WELL AS WITHIN THE SYSTEM, AND ALSO PROVIDES NOVEL GUIDE MEANS FOR GUIDING A GLOAT AND PREVENTING DAMAGE FROM SURGING. WHEN FLOODING CONDITIONS EXIST, A FLOAT MEBER RISES WITH THE LVEL OF THE SEWAGE, AND IN TURN, CAUSES A VALVE TO CLOSE IN THE SEWER PIPE, THERBY PREVENTING ANY FLOW OF SEWAGE THROUGH THE PIPE. WHEN FLOODING CONDITIONS SUBSIDE, THE FLOAT IS CORRESPONDINGLY LOWERED WITH THE LEVEL OF SEWAGE AND THE VALVE IS OPENED.

Sept. 20, 1911 L, HER 3,605,799

SEWER FLOODING CONTROL SYSTEM Filed April 24, 1970 4 Sheets-Sheet 1 I NVENTOR,

FIE] 1.1.01 0 G. cmse/vls BY Y ATTOE/VEV Sept. 20, 1911 Filed April 24, 1970 L. G. CHERNE 4 Sheets-Sheet 3 .I-JO6 1 16 121 119 H I ii 115 111 51 [7B5 INVENTOR.

United States Patent 3,605,799 SEWER FLOODIN G CONTROL SYSTEM Lloyd G. Cherne, 5704 View Lane, Minneapolis, Minn. 55424 Filed Apr. 24, 1970, Ser. No. 31,586 Int. Cl. F16k 31/26 US. Cl. 137-413 Claims ABSTRACT OF THE DISCLOSURE An improved sewer flooding control system utilized to prevent the flooding of a building basement because of a backup in the building sewer or the surging of sewage in the sewer. The improved sewer flooding control system is mounted below the floor level of a basement to be protected and is actuated by the presence of sewer flooding conditions in the sewer. The improved system also provides novel means for preventing flooding or damage as a result of surging sewage both in the basement as well as within the system, and also provides novel guide means for guiding a float and preventing damage from surging. When flooding conditions exist, a float member rises with the level of the sewage, and in turn, causes a valve to close in the sewer pipe, thereby preventing any flow of sewage through the pipe. When flooding conditions subside, the float is correspondingly lowered with the level of sewage and the valve is opened.

BACKGROUND OF THE INVENTION This invention relates to a sewer flooding control system and more particularly to a system which prevents basement flooding due to sewer backup, as a result of excessive precipitation or other similar causes, or as a result of the surging of the backup sewage.

During the normal operation of a building drainage system, the waste water or sewage flows by gravity from a floor drain, through a building sewer and into a street sewer to be carried away with other sewage. Under certain conditions, especially during heavy rainstorms, the level of sewage in the street sewer is quite high, and in some cases, is higher than the level of the floor drain. When this occurs, the drainage process is reversed and sewage flows from the sewer through the floor drain and into the basement to cause flooding. The general purpose of a sewer flooding control system is to prevent this type of backup flooding.

In the past, several types of sewer flooding control systems have been used to prevent the backup of sewage into basements or other areas where the area in question was connected to the sewage system by means of a conventional floor drain. Although these systems operated satisfactorily to prevent flooding, the protection against surging was incomplete and the systems themselves were often in need of repair or maintenance.

Prior sewage control systems generally comprised a base or sewage receiving drum mounted to and in communication with a section of the building sewer pipe, a float within the drum designed to rise and fall in response to the flooding conditions of the building sewer, and a valve in the building sewer line that closed and opened in response to the rise and fall of the float respectively. With these members, the backup of sewage as a result of sewer flooding was prevented.

The bases or sewage receiving drums of prior control systems often were constructed of cast metal to which various types of sewage easily adhered. Particularly, sewage having a greasy consistency often accumulated on the bottom sides of the base as the backup sewage retreated. After several floodings, this accumulation began to interfere with the movement of the float contained in the drum. Eventually, the accumulation was suflicient to render the float immovable, thereby causing the sewer valve to remain in a closed position. This position, although still preventing sewer flooding, also prevented the prior systems from operating properly when flooding conditions had subsided.

The floats in the prior systems were usually partially made of brass. These brass floats had a tendency to shatter easily, especially during surging when the float was forced up by a surge of the sewage, and then allowed to drop to the bottom side of the base as the sewage retreated. The shattered or cracked floats increased the maintenance costs of the system, and caused it to malfunction.

Furthermore, the protection against sewer flooding in prior systems was incomplete in that it did not provide for protection against surging. The sewer valve normally takes a substantial time (usually from 15-30 seconds) to close once the backup sewage, and thus the float, has reached a sufliciently high level. As a result, the prior systems offered no protection for the surge that came in quickly, and then rapidly retreated. This surging caused sewage to flow through the drain pipes and splash up through the floor drain into the basement.

SUMMARY OF THE INVENTION In contrast to prior sewer flooding control systems, the improved system of the present invention requires only infrequent cleaning and very little maintenance and repair. In the present system, the base or the sewage receiving drum is made of polyethylene thereby providing a surface to which the sewage cannot adhere. In addition, the bottom side of the base slopes at an angle of about forty-five degrees with the horizontal, since it has been found that if the bottom side has this angle, the sewage and grease are prevented from accumulating on the bottom side of the base as in the prior systems.

The float contained in the base portion of the system is also made of polyethylene and filled with solid polyfoam. This structure provides for a longer lasting float that will not be subject to corrosion or oxidation, and will not shatter as a result of continuous or extended surging. In addition, means are provided for guiding the float in its up and down movement within the base to prevent a surging force from causing the float to come in contact with the side walls of the base.

Also, the present invention provides for a flap valve to be placed in the basement sewer line so that the surging of the sewer will not cause sewage to be forced through the drain into the basement. By installing this flap valve, the normal flow of sewage from the floor drain to the street sewer is not deterred. However, a sudden surge of sewage from the street sewer toward the floor drain will be substantially prevented by the valve so that no sewage will enter the basement through the floor drain while the basement sewer valve is closing. The flap valve is also designed to dissipate the energy of a surge of sewage and to prevent sewage from splashing into a basement as a result of that surge.

For a similar reason, an anti-splash plate is mounted between the bottom opening of the system base, which opens into the basement sewer, and the float within the base. This anti-splash plate prevents the surging sewage from splashing against the float, and dissipates the surging force so that the movement of the float is gradual.

Particularly, the sewer flooding control system of the present invention includes a base or sewage receiving drum along with a float whose movement responds to the level of the sewage in the drum. The base is in direct communication with the basement sewer line, thus the movement of the float is directly associated with the level oi the sewage in the basement sewer. A valve opening and closing means is associated with the float so that movement of the float causes the valve to be opened or closed, thereby allowing or preventing, respectively, the sewage from passing through the basement sewer line. When the sewage in the base is at a high level so that the float is at its uppermost position, the valve is closed, thereby preventing the backup sewage from passing through the basement sewer into the basement. When the sewage in the base is such that the float is not at its uppermost position, the valve is open, thereby permitting waste to flow from the floor drain through the basement sewer and into the street sewer. In addition, the control system includes a leak detector to detect leaks in the base and float apparatus.

Accordingly, it is a primary object of the present invention to provide an improved sewer flooding control system which is relatively free from maintenance and which prevents the adherence and accumulation of sewage to the sides and bottom of the sewage receiving base.

Another object of the present invention is to provide an improved sewer flooding control system with means to prevent sewage from entering the basement either as a result of the surging force of backup sewage or as a result of the length of time necessary to close the sewer valve when the level of sewage in the basement sewer is sufficiently high.

Also, it is an object of the present invention to provide a float of a construction which prevents easy shattering as a result of constant and repeated surging.

Another object of the present invention is to provide an improved sewer flooding control system with means to prevent sewage from forcefully contacting the float as a result of surging force of the backup sewage.

It is also an object of this invention to provide a float guide means which prevents contact between the float member and the side walls of the base.

A further object of the present invention is to provide a sewer flooding control system with a leak detector and a monitor system to afford maximum protection against flooding.

These and other objects and advantages of the invention will become apparent from the following description of the preferred embodiment and upon reference to the drawings and the appended claims.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the entire sewer flooding control apparatus as it is installed, ready for use. I

FIG. 2 is a partial sectional view of the base and main cylinder portion of the system.

FIG. 3 is a partial sectional view of the piston and flap valve apparatus.

FIG. 4 is a detailed perspective view of the four-way valve and the actuator arm connection.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. I, the preferred embodiment of the sewer flooding control apparatus 13 comprises a section of basement sewer pipe 10, a base 11., a cylinder 24 and a knife valve assembly 18. The entire system is installed in a pit area 19 in the basement, so that the pipe section and the base '11 is below the level of the basement floor 20. The pipe section 10 is connected at one end to a basement sewer pipe 15 extending from the control apparatus 13 to the area which is to be drained (not shown), and is connected at the other end to a basement sewer pipe 16 exte d ng from the apparatus 13 past the wall 21 to a street sewer (not shown). During normal conditions, when flooding conditions do not exist, the level of sewage in the street is below the basement floor level and thus sewage is drained from the basement through the pipes 15, 10 and 16, and into the street sewer. When flooding conditions exist, the level of sewage in the street sewer is higher than the basement level. Therefore, the normal flow of sewage is from the street sewer into the basement area. During flooding conditions, the system is actuated to prevent flow from the street sewer to the basement area.

The base 11, having an opening 63 in communication with the top of the pipe section 10, is secured tightly to the pipe 10 by means of a U-bolt 22 extending around the pipe 10. A float 26 is contained within the base 11 and is designed to correspond with the sewage level in the street sewer. Under normal conditions, sewage flows through the pipe 10, without entering the base, and into the street sewer. During flooding conditions, however, the high level of sewage in the street sewer causes sewage to back up through the opening 63 and into the base 11 and causes the float 26 to rise to its uppermost position, thereby actuating the knife valve assembly 18 to move toward a down or closed position.

A cylinder portion 24 extends above the base 11 and houses an activator rod 25 which extends from the float 26 contained in the base 11 past the cap 34 on top of the cylinder 24. The float 26 and thus the rod 25 rise and fall in response to the level of the sewage in the base 11, as will be described more fully later on, to actuate a conventional four-way valve 28 and thus the knife valve assembly 18.

The knife valve assembly 18 as seen in FIG. 1, includes a piston housing 29, support brackets 30*, and an adapter 31. The adapter allows the knife assembly 18 to be connected to the sewer pipe .10 so that the flow of sewage through the pipe 10 may be prevented. During normal conditions the valve is in an up position, i.e., thereby allowing the sewage to flow from the basement to the sewer. During flooding conditions, the valve is in a down position, i.e., so that sewage may not back up from the street sewer into the basement.

A conventional leak detector is positioned in a sump 36 to detect leaks in the system. An ordinary leak detector which can be used for this purpose is the ENPO 1600 series lea-k detector, which includes a submersible pump 38 and liquid level sensor 40. When a leak occurs in the system, the leakage flows into the sump 36. When the level of leakage in the sump 36 reaches a suflicient level, usually several inches, the sensor 40, which is sensitive to the the level of liquid in the sump 36, activates the pump 38 which then pumps the sewage in the sump through the pipe 39, and back into the pipe 10. When the level of the sewage in the sump 36 has been sufficiently lowered, the pump 38 is turned ofl" by the sensor 40. Even when the pump 38 is turned off, a sufficient level of liquid remains in the sump 36 to prevent the escape of sewer gas through the pipe 39 and into the basement.

A vent 41. is provided for the base 11 to allow any sewer gas to be vented out of the building. A vent connection 42 connects the base 11 to one branch of a Y 44, which in turn is connected to a vent pipe 45 extending out of the building. A plug 46 and a rod 48 are connected to the downwardly extending portion of the Y 44 so that the vent pipe 45 may be anchored to the pipe 10 and so that it may be easily cleaned and drained.

Referring now to FIG. 2, the connection of the base 11 and the cylinder 24 to the pipe 10 may be seen. The side walls of the base 11 are substantially vertical and are fastened at the top to a bottom flanged portion 56 of the cylinder 24. The bolts 58 positioned around the perimeter of the flanged portion 56 secure the portion 56, a side wall flange 59, and a gasket 52 therebetween in a tight relationship to effectively seal the base 11.

The bottom portion of the side wall 60 slopes toward the opening in the sewer pipe and has been found to be very effective in preventing sewage, particularly that of a greasy consistency, from accumulating on the bottom side 60 and thereby preventing the system 13 (FIG. 1) from operating properly. The applicant has found that the bottom side 60 should slope at an angle of at least forty-five degrees to prevent such accumulation.

The opening 63 at the bottom of the base 11 is in direct communication with a flanged opening 67 in the pipe '10. A dome adapter clamp 65, the bottom flange of the base 61, and the bottom flange 73 of the anti-splash plate 62, are held in a tight, sealed relationship, with gaskets 64, 64 positioned therebetween by bolts 66. The adapter clamp 65, and thus the entire base and cylinder, are then secured to the flanged opening 67 in the pipe 10 with a gasket 51 positioned therebetween by means of the U-bolt 22 extending around the pipe 10. With this arrangement, the sewage, under normal conditions, flows from the basement floor drain, through the pipe 10, and into the street sewer. During flooding conditions, sewage backs up from the street sewer, through the opening 63, and into the base 11 to raise the float 26.

A baflle or anti-splash plate 62- is mounted immediately above the opening 63 and is supported by several rods 77 which in turn are secured to the flange 63. The principal purpose of the plate 62 is to dissipate the surging force of the backup sewage and to serve as a support for the float guide 71. As seen in FIG. 2, the outer circumferential edge of the plate 62 is in spaced relation to the sloping side 60 so that sewage is free to back up into the base and raise the float 26. As a result of the anti-splash plate 62, the up and down movement of the float 26 is gradual even though sewage may be surging through the opening 63.

A float 26 is contained within the base 11 and has an outer plastic shell surface preferably made of polyethylene. The interior of the shell is filled with polyfoam to give the float durability and additional buoyancy. A center opening 69, within the float 26 and defined by the wall 54, extends between two metal ends 70, 70 to slide over a float guide 71 which extends from, and is mounted to, the baifle 62. The guide 71 guides the float 26 in its up and down movement and prevents the float 26 from being forced against the base walls 11, 60 by the surging force of the sewage. The guide 71 is of a suflicient length so that when the float 26 is in its uppermost position, (when the gasket 72 is tightly sealed against the bottom 74) the upper end of the guide 71 is still within a portion of the center opening 69.

A resilient gasket 72 is secured on top of the metal end 70 at the top of the float 26 and is designed to engage the cylinder bottom wall 74 which separates and seals the base 11 and the cylinder 24. An upstanding float guide tube 75 extends upward from the center of the bottom wall 74 and provides, at its bottom end, an insert for an activator rod guide 76, positioned around the rod 25, and immediately above the gasket 72'. When the float 26 is raised by the level of the sewage in the base '11, the guide 76 moves into the lower end of the tube 75 to properly orientate and seat the gasket 72 against the bottom 74, and to prevent the passage of any sewage into the cylinder through the tube 75.

An inverted cup member 78 is carried by the activator rod 25 immediately above the top of the upstanding tube 75, so that when the float 26 is in its lowest position, the bottom edges of the cup member 78 extend over and around the tube 75, and terminate just above the bottom 74. The top of the tube 75 is provided with a center opening 57 which serves as a guide for the rod 25. Several holes 79 are contained in the walls of the tube 75 a short distance from the top to allow the water which collects in the cylinder 24 to drain into the sewer pipe 10.

The combination of the upstanding tube 75 and the inverted cup 78 functions primarily as a sewer gas trap to prevent the escape of sewer gas from the base 11, to

the cylinder 24, and into the basement. If this arrangement was not present, the sewer gas from the building and street sewer would freely pass through the base 11 and the cylinder 24, and into the basement. However, by maintaining a sufficient level or water in the cylinder 24, the escape of sewer gas is prevented. As seen, the holes 79 are positioned a spaced distance above the bottom of the cylinder 74. Thus, the level of water in the cylinder 24 is maintained at this height, with the excess being drained through the holes 79 and into the base 11. At all times during the movement of the float 26, the bottom edges of the inverted cup 78 are immersed in the water in the cylinder 24, so that the sewer gas passing up through the tube and through the holes 79, is prevented from escaping. In order for the cup 78 to be effective as a gas trap, the portion of the cup 78 extending below the holes 79, when the float 26 is in its lowest position, must have a length greater than the distance of the travel of the float 26 between its lowest position and its uppermost position.

An integral funnel 80 is provided at the top of the cylinder 24 to receive drain water from the operation of the piston 29 (FIG. 1) by way of the tubing 84 and 85. This water is then directed by the funnel 80 into the cylinder 24 to provide the level of water for the gas trap members 78 and 79.

A cap 34 is provided at the top of the cylinder 24 to cover the cylinder and to provide a mounting base for a valve mounting bracket 86. Both the cap 34 and the bracket 86 have a hole extending therethrough from the axial center of the cylinder 24 to provide a guide for the up and down movement of the rod 25. A conventional four-way valve 28 is mounted to the bracket 86 along with several tubings whose function will be described later.

Referring now to FIG. 4, a conventional four-way valve 28 and the means for transferring the up and down movement of the rod 25 to the valve .28 is shown. A typical four-way valve is a Versa, VNH4312. As can be seen, the rod 25 extends through the cap 34 and the bracket 86, and well above the top of the cylinder 24'.

An actuator arm 88 has a single prong end 93 securely fastened to a pivotable member 89 of the valve 28, so that when the arm 88 is pivoted in a vertical plane, the member 89 is pivoted, thereby controlling the operation of the four-way valve 28. A bifurcated end 97 of the arm 88 extends past the rod 25 and is oriented so that the two prongs of the end 97 straddle the rod 25. The distance between the two prongs is only slightly greater than the diameter of the rod 25, thus the only possible movement of the arm 88 is vertical pivotal movement about the member 89.

An actuator arm stop 90 is immovably secured to the rod 25 immediately above the bifurcated end 97. Two additional stops 91 and 92 are mounted to the rod 25 below the two prongs of the arm 88, with a coil spring 94 positioned therebetween. Both of the stops 90 and 91 have a diameter greater than the distance between the prongs of the bifurcated end 97, so that vertical movement of the rod 25 will cause the actuator arm 88, acting through the stops 90 and 91, to be urged toward respective pivotal movement about the member 89. The stop 92 is securely mounted to the rod 25 and serves as a base for the coil spring 94. The stop 91 is slidably mounted on the rod 25 immediately above the spring 94 and immediately below the arm 88. The stops 90, 91 and 92 serve to transfer the up and down movement of the rod 25 to the arm 88, so that when the rod 25 moves up, the stops 91 and 92 and the spring 94 causes the arm 88 to pivot upwards about the member 89. When the rod 25 moves down, the stop 90 causes the arm 88 to pivot downwardly about the member 89.

The spring 94 positioned between the stops 91 and 92 allows for limited upward movement of the rod 25 without any pivotal movement of the arms 88. Thus, a limited amount of surging may occur in the base 11 (FIG. 2), thereby causing a small upward movement of the float 26 (FIG. 2) and the rod 25, without causing the arm 88 to move. In addition, the spring 94 serves as a cushion to prevent the sudden jarring of the actuator arm 88 as a result of the sudden upward movement of the rod 25 due to rapid flooding or extensive surging.

The operation of the four-way valve 28 controls the flow of water from the tubing 55 to either of the tubings 81 or 82. In this manner the movement of the piston 99 (FIG. 3) may be controlled. The tubings 84 and 85 are associated respectively with the tubings 81 and 82 to act as outlets for water passing from the tubes 81 and 82. The actual function of each tubing will be described more fully when the operation of the entire control system is discussed. The valve 28 also serves to direct the spent water from the piston 29 (FIG. 1) into the funnel 80 to be used in cooperation with the gas trap apparatus, the tube 75 and the cup 78 (FIG. 2), as previously discussed.

The tubing 55 contains water under normal tap water pressure and extends into the valve 28 to eventually connect with either of the tubings 81 or 82. A spigot 83 is connected into the tubing 55 with a piece of plastic tubing 87 leading from the spigot 83 to the leak detector sump 36 (FIG. 1). The purpose of this arrangement is to allow someone to periodically check the level of the water in the sump 36, and if necessary, run some water into the sump so that it is at a sufficient level. Often, the leak detector 35 is not called upon to operate for several months either as a result of no flooding conditions or as a result of no leaks in the base 11. When this happens, the level of water normally maintained in the sump 36 evaporates, thereby allowing sewer gas to back up into the basement. By periodically checking, the level of Water in the sump 36 may be maintained by turning the spigot 83 to allow water to flow through the tube 87 into the sump 36.

Referring to FIG. 3, the construction of and the relationship between the knife valve assembly 18 and the flap valve assembly 95 may be seen. The piston housing 29 along with the upper and lower end plates 96 and 98 combine to form a piston chamber which houses a piston 99 and consists of an upper and lower portion 100 and 101. The entire construction including the housing 29 and end plates 96 and 98 is supported by the stand or support bracket 30 which extends from the pipe to the bottom plate 98, and is further supported by means of a piston stand 102 and a band clamp 104 extending around the cylinder 24.

The piston 99 is mounted to the end of a piston rod or push rod 105 which extends from the piston 99 to the knife valve 106. As can be seen from the partially broken away view of the piston housing 29 in FIG. 3, the size of the upper and lower chambers 100 and 101 changes with the relative vertical position of the piston 99. Passageways 108 and 109 are contained in the upper and lower end plates 96 and 98 respectively so that the chambers 100 and 101 are respectively in communication with the tubings 81 and 82. The tubings 81 and 82 extend from the passages 108 and 109 to the four-way valve 28 of FIG. 4.

The vertical movement of the piston 99 is a result of the flow of water, under normal tap water pressure, flowing from either of the tubings 81 or 82 into their respective chambers 100 and 101. When water flows from the tubing 81 into the chamber 100, the piston 99 is forced downwardly thus causing the rod 105 to move the knife valve into a closed position. At the same time, the water in the chamber 101 is being forced out through the tubing 82 to accommodate the downward movement of the piston 99. When the water flows into the chamber 101 from the tubing 82, the above process is reversed. The piston 99 and rod 105 are moved upwardly as a result of the tap water pressure in the chamber 101,

causing the knife valve 106 to move to an open position and the water in the chamber to be forced out through the tubing 81. After the valve 106 has assumed its open position, it is maintained in this position, along with the piston 29 and the rod by the normal water pressure in the chamber 101. In the preferred embodiment of FIGS. 1 and 3, the piston 29 is located above the building pipe 10.

The lower portion of the knife valve assembly 18 is connected to the sewer pipe 10 by means of an adapter 31 and a pair of flange portions 110 of the pipe 10. The adapter 31 and the flange portions 110 are held in a tight sandwich relationship by bolts 111 to effectively seal the pipe 10 and to allow the knife valve 106 to properly move between an open or closed position to thereby permit or prevent the passage of sewage through the pipe 10.

The flap valve assembly 95 is located a short distance from the knife valve assembly 18 and includes a cleanout T 112, a flap valve seat 114, and a flap plate 115. The T 112 has one end connected to the pipe 15 which extends to the basement drain (not shown), and another end connected to the pipe 10 which extends to the street sewer (not shown). The end connected to the pipe 15 has a thickened portion 116 which terminates in a shoulder portion 118. The shoulder 118 provides a mounting surface for the flap valve seat 114 which in turn provides a seat for the flap plate 115. The seat 114 is leaded into the shoulder 118 so that when the flap plate is hanging free, a slight opening is present between the plate 115 and the seat 114. The position of the plate 115 in FIG. 3 is the position it assumes when sewage is flowing from the basement under normal conditions.

A hinge 119 to pivotally mount the plate 115 is provided at the uppermost part of the seat 114 in a position which does not interfere in any way with the passage of sewage through the pipe 10. The pivotal mounting allows the plate 115 to hang freely and to allow a normal flow of sewage through the valve 95 in a direction from the basement to the sewer. The purpose of the valve assembly 95 is to prevent the sewage, due to surging, from moving through the pipe 15 and splashing up through the floor drain (not shown) and into the basement. With the presence of the flap valve 95, the surging force of the sewage is dissipated, thereby preventing the surge from entering the basement.

A clean-out cover 120 is fastened to a flange portion 121 on the T branch of the T 112. By removing the cover 120, the pipe in the area of the valve 95 may be cleaned and any repair or maintenance of the plate 115 or seat 114 may be taken care of.

The operation of the sewer flooding control system may best be seen by general reference to FIG. 1 and particular reference to FIGS. 2, 3 and 4. Referring first to FIG. 1, when the level of the sewage in the street sewer is lower than the pipes 15, 10 and 16, the sewage flows normally from the basement to the sewer. In this condition the knife valve (FIG. 3) is in an open position. When the sewage level in the sewer rises to a level above that of the basement floor 20 the tendency is for the sewage to back up through the pipes 15, 10 and 16 and into the basement. However, the operation of the control system 13 prevents such basement flooding as hereinafter described.

When flooding conditions exist, the sewage backs up from the sewer into the base 11 to raise the float 26. As the float 26 is raised, the rod 25 is likewise raised causing the actuator arm 88 (FIG. 4) to be pivoted upward. When the float 26 reaches its uppermost position so that the gasket 72 is sealed against the bottom 74, to prevent sewage from passing into the cylinder 24, the arm 88 is also in its highest pivotal position. When the arm 88 is in this position, the four-way valve 28 is moved to a position wherein water is caused to flow from the tubing 55 into the tubing 81.

As the water passes from the tubing 81 through the passage 108 and into the chamber 100 (FIG. 3), the piston 99 is caused to move downward, thereby causing the push rod 105 and the knife valve 106 to be moved into a closed position. When the knife valve is in this position, sewage is prevented from flowing from the sewer into the basement. Also, as the piston 99 is moving downward, the water in the chamber 101 is forced through the passage 109 and the tubing 82, into the valve 28 (FIG. 4) and out through the tubing 85 to be directed into the funnel 80.

When the flooding condition has subsided, the level of the sewage in the base 11 recedes, thereby causing the float 26 and the rod to be lowered. As the rod 25 is lowered, the arm 88 (FIG. 4) is pivoted downwardly thereby resulting in the valve 28 being actuated in 'a manner which causes the water in the tubing 55 to be directed into the tubing 82. When this happens, water passes through the passage 109 and into the chamber 101 thereby causing the piston 99, the rod 105, and the knife valve 106 to move upward to an open position. This position of the knife valve 106 allows sewage to again flow normally from the basement floor to drain the sewer. As the piston 99 is moving upward, the water is being forced out of the chamber 100, through the tubing 81 and into the valve 28. From here it is directed to the tubing 84 for drainage into the funnel 80.

It is suggested that a monitor system may 'be provided in conjunction with the above-described embodiment so that particular information about the operating status of each of the functioning units of the system may be monitored to locations remote from the site of the control system. For example, the actuation of the four-way valve 28 (FIG. 4), the closing of the knife valve assembly 18 (FIG. 3), the operation of the leak detector 35 (FIG. 1), or the recognition of low or negative water pressure in the water supply system may be so monitored. This would allow a supervisor or other appropriate person to more easily know of the condition of the sewer (flooded or otherwise), without posting a constant vigilance at the site of the flooding control system.

This invention may be embodied in other forms not specifically shown in the preferred embodiment without departing from the spirit or essential characteristics thereof. The preferred embodiment is therefore to be considered as illustrative only, with the scope of the invention being indicated by the appended claims and their equivalents.

What is claimed and desired to be secured by the United States Letters Patent is:

1. An improved sewer flooding control system for selectively actuating a valve member into a closed and open position with respect to drainage through a basement sewer drain pipe so as to prevent the flooding of basements or other areas as a result of flooding conditions in the street sewer comprising:

a drain pipe extending between, and in communication with, the basement drain and the street sewer;

a valve member operatively positioned in said drain pipe, the valve member having an open position for allowing the normal flow of sewage from the basement drain to the street sewer and a closed position for preventing the backup of sewage from the street sewer toward the basement drain;

means contained within said drain pipe between the valve member and the basement drain for dissipating the surging force of backup sewage passing therethrough, said means having a valve seat integrally formed with the drain pipe and extending around the inner periphery thereof and a valve plate designed to be disposed against the valve seat to provide an effective seal in said drain pipe, the disposition of the valve plate against said valve seat resulting from the force of the backup sewage passing from the street sewer toward the basement drain;

a dome portion mounted to said drain pipe defining a first chamber for receiving a limited amount of sewage from the drain pipe, said dome portion having:

a bottom opening sealed to and in communication with the drain pipe so that sewage may pass from the drain pipe into said first chamber and assume a level in said first chamber equivalent to that of the sewage level in the street sewer,

a side wall 'with an upper portion having a circumference substantially greater than the circumference of said bottom opening and a lower portion having a lower end comprising an inwardly sloping surface extending from the upper portion to said bottom opening, the inwardly sloping surface designed to prevent the accumulation of sewage thereon, and

sealing means at the top of the dome portion for limiting the amount of sewage passing into said first chamber from the drain pipe;

at float contained within said dome portion and carried by a float rod for reciprocal vertical movement, the float having an outer diameter substantially less than the inner surface of said wall so that during the vertical movement of said float, the float is spaced from the inner surface of said side wall, said float being of sufficient buoyancy to rise and fall with the level of sewage in said dome portion, and thereby move the float into an upper and lower position, said upper position being defined by the position of the float in its highest position and said lower position being defined by the position of the float in its lowest position;

a plate member mounted between the float and the drain pipe, and immediately above said bottom opening, the size of the plate member being sufiicient to dissipate the surging force of sewage passing through the bottom opening and into said first chamber, but spaced from said side Wall to allow sewage to flow between the side wall and the plate and thereby cause the float to move to an appropriate position; and

means for controlling the position of said valve member in response to the rise and fall movement of the float so that when the float is in its upper position, the valve member is in said closed position, and when the float is moved away from its upper position, the valve member is in said open position.

2. The improved sewer flooding conrol system of claim 1 wherein said means for controlling the position of said valve member in response to the rise and fall movement of the float includes actuating valve means operatively connected between the float rod and said valve member in the drain pipe.

3. The sewer flooding control system of claim 2 and a float guide means including a vertical rod mounted to said plate member for guiding the float in its up and down movement.

4. The improved sewer flooding control system of claim 2 and means for operatively connecting said actuating valve means to the float rod including an actuator arm having a single prong end pivotally mounted to said actuating valve means and a bifurcated end whose two prongs straddle the float rod, and means for transferring the reciprocal movement of said float rod to the bifurcated end.

5. The sewer flooding control system of claim 4 wherein the sloping surface is disposed at approximately fortyfive degrees with respect to the horizontal.

6. The sewer flooding control system of claim 5 and a float guide means including a vertical rod mounted to said plate member for guiding the float in its up and down movement.

7. The sewer flooding control system of claim 1 wherein the inwardly sloping surface of said side wall is disposed at approximately forty-five degrees with respect to the horizontal.

8. The sewer flooding control system of claim 1 and a float guide means mounted to said plate member for guiding the float in its up and down movement.

9. The sewer flooding control system of claim 8 wherein the float guide means includes a vertical rod.

10. The sewer flooding control system of claim 9 wherein the sloping surface is disposed at approximately forty-five degrees with respect to the horizontal.

References Cited UNITED STATES PATENTS HENRY T. KLINKSIEK, Primary Examiner D. R. MATTHEWS, Assistant Examiner US. Cl. X.R. 

